If you have a stiff lower back or tight hamstrings, try the Roll Back & Reach.
This exercise is typically used as a warm up activity. But due to its ballistic nature, this exercise should be performed after your warmup. (Your limbs should be loose before you get all up in this one.) Alternatively, it can be used as a “break” during high intensity workouts. For example, 10 burpees, 10 split jumps, 5 roll to reach, repeat.
Focus area: hamstrings, lower back, groin/inner thigh
Improves: flexibility and mobility of the focus areas
Please remember to only do this exercise after you have warmed up. Otherwise, you will injure thine secret parts. And, you don’t want that. You don’t.
Also, if you work with kids or teens, this is a good exercise for them. There’s enough “fun” to distract them from the work. Don’t you dare tell them how effective it is, it’ll ruin the fun.